Etching control method and etching control system

The invention provides an etching control method and an etching control system capable of reducing operation cost of a process. The etching control method comprises a step a, a step b and a step c. In step a, shape data including information on the height of a ring assembly measured at a plurality of positions on the surface of the ring assembly is collected, and the ring assembly is disposed so as to surround a region on a mounting table on which a substrate is mounted. In step b, a control amount capable of controlling the sheath distribution in the vicinity of the ring assembly is determined from the shape data collected in step a using a relationship model indicating the relationship between the shape data collected in advance and the control amount. The angle of inclination of the recess formed in the substrate by plasma etching becomes an angle within an allowable range. In step c, the sheath distribution in the vicinity of the ring assembly is controlled by applying the determined control quantity. 本发明